diff options
Diffstat (limited to 'src/diff.c')
| -rw-r--r-- | src/diff.c | 1472 |
1 files changed, 1472 insertions, 0 deletions
diff --git a/src/diff.c b/src/diff.c new file mode 100644 index 0000000..686945e --- /dev/null +++ b/src/diff.c @@ -0,0 +1,1472 @@ +/* diff - compare files line by line + + Copyright (C) 1988-1989, 1992-1994, 1996, 1998, 2001-2002, 2004, 2006-2007, + 2009-2013, 2015-2016 Free Software Foundation, Inc. + + This file is part of GNU DIFF. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#define GDIFF_MAIN +#include "diff.h" +#include <assert.h> +#include "paths.h" +#include <c-stack.h> +#include <dirname.h> +#include <error.h> +#include <exclude.h> +#include <exitfail.h> +#include <filenamecat.h> +#include <file-type.h> +#include <fnmatch.h> +#include <getopt.h> +#include <hard-locale.h> +#include <prepargs.h> +#include <progname.h> +#include <sh-quote.h> +#include <stat-time.h> +#include <timespec.h> +#include <version-etc.h> +#include <xalloc.h> +#include <xreadlink.h> +#include <binary-io.h> + +/* The official name of this program (e.g., no 'g' prefix). */ +#define PROGRAM_NAME "diff" + +#define AUTHORS \ + proper_name ("Paul Eggert"), \ + proper_name ("Mike Haertel"), \ + proper_name ("David Hayes"), \ + proper_name ("Richard Stallman"), \ + proper_name ("Len Tower") + +#ifndef GUTTER_WIDTH_MINIMUM +# define GUTTER_WIDTH_MINIMUM 3 +#endif + +struct regexp_list +{ + char *regexps; /* chars representing disjunction of the regexps */ + size_t len; /* chars used in 'regexps' */ + size_t size; /* size malloc'ed for 'regexps'; 0 if not malloc'ed */ + bool multiple_regexps;/* Does 'regexps' represent a disjunction? */ + struct re_pattern_buffer *buf; +}; + +static int compare_files (struct comparison const *, char const *, char const *); +static void add_regexp (struct regexp_list *, char const *); +static void summarize_regexp_list (struct regexp_list *); +static void specify_style (enum output_style); +static void specify_value (char const **, char const *, char const *); +static void specify_colors_style (char const *); +static void try_help (char const *, char const *) __attribute__((noreturn)); +static void check_stdout (void); +static void usage (void); + +/* If comparing directories, compare their common subdirectories + recursively. */ +static bool recursive; + +/* In context diffs, show previous lines that match these regexps. */ +static struct regexp_list function_regexp_list; + +/* Ignore changes affecting only lines that match these regexps. */ +static struct regexp_list ignore_regexp_list; + +#if O_BINARY +/* Use binary I/O when reading and writing data (--binary). + On POSIX hosts, this has no effect. */ +static bool binary; +#else +enum { binary = true }; +#endif + +/* If one file is missing, treat it as present but empty (-N). */ +static bool new_file; + +/* If the first file is missing, treat it as present but empty + (--unidirectional-new-file). */ +static bool unidirectional_new_file; + +/* Report files compared that are the same (-s). + Normally nothing is output when that happens. */ +static bool report_identical_files; + +static char const shortopts[] = +"0123456789abBcC:dD:eEfF:hHiI:lL:nNpPqrsS:tTuU:vwW:x:X:yZ"; + +/* Values for long options that do not have single-letter equivalents. */ +enum +{ + BINARY_OPTION = CHAR_MAX + 1, + FROM_FILE_OPTION, + HELP_OPTION, + HORIZON_LINES_OPTION, + IGNORE_FILE_NAME_CASE_OPTION, + INHIBIT_HUNK_MERGE_OPTION, + LEFT_COLUMN_OPTION, + LINE_FORMAT_OPTION, + NO_DEREFERENCE_OPTION, + NO_IGNORE_FILE_NAME_CASE_OPTION, + NORMAL_OPTION, + SDIFF_MERGE_ASSIST_OPTION, + STRIP_TRAILING_CR_OPTION, + SUPPRESS_BLANK_EMPTY_OPTION, + SUPPRESS_COMMON_LINES_OPTION, + TABSIZE_OPTION, + TO_FILE_OPTION, + + /* These options must be in sequence. */ + UNCHANGED_LINE_FORMAT_OPTION, + OLD_LINE_FORMAT_OPTION, + NEW_LINE_FORMAT_OPTION, + + /* These options must be in sequence. */ + UNCHANGED_GROUP_FORMAT_OPTION, + OLD_GROUP_FORMAT_OPTION, + NEW_GROUP_FORMAT_OPTION, + CHANGED_GROUP_FORMAT_OPTION, + + COLOR_OPTION, + COLOR_PALETTE_OPTION, + + PRESUME_OUTPUT_TTY_OPTION, +}; + +static char const group_format_option[][sizeof "--unchanged-group-format"] = + { + "--unchanged-group-format", + "--old-group-format", + "--new-group-format", + "--changed-group-format" + }; + +static char const line_format_option[][sizeof "--unchanged-line-format"] = + { + "--unchanged-line-format", + "--old-line-format", + "--new-line-format" + }; + +static struct option const longopts[] = +{ + {"binary", 0, 0, BINARY_OPTION}, + {"brief", 0, 0, 'q'}, + {"changed-group-format", 1, 0, CHANGED_GROUP_FORMAT_OPTION}, + {"color", 2, 0, COLOR_OPTION}, + {"context", 2, 0, 'C'}, + {"ed", 0, 0, 'e'}, + {"exclude", 1, 0, 'x'}, + {"exclude-from", 1, 0, 'X'}, + {"expand-tabs", 0, 0, 't'}, + {"forward-ed", 0, 0, 'f'}, + {"from-file", 1, 0, FROM_FILE_OPTION}, + {"help", 0, 0, HELP_OPTION}, + {"horizon-lines", 1, 0, HORIZON_LINES_OPTION}, + {"ifdef", 1, 0, 'D'}, + {"ignore-all-space", 0, 0, 'w'}, + {"ignore-blank-lines", 0, 0, 'B'}, + {"ignore-case", 0, 0, 'i'}, + {"ignore-file-name-case", 0, 0, IGNORE_FILE_NAME_CASE_OPTION}, + {"ignore-matching-lines", 1, 0, 'I'}, + {"ignore-space-change", 0, 0, 'b'}, + {"ignore-tab-expansion", 0, 0, 'E'}, + {"ignore-trailing-space", 0, 0, 'Z'}, + {"inhibit-hunk-merge", 0, 0, INHIBIT_HUNK_MERGE_OPTION}, + {"initial-tab", 0, 0, 'T'}, + {"label", 1, 0, 'L'}, + {"left-column", 0, 0, LEFT_COLUMN_OPTION}, + {"line-format", 1, 0, LINE_FORMAT_OPTION}, + {"minimal", 0, 0, 'd'}, + {"new-file", 0, 0, 'N'}, + {"new-group-format", 1, 0, NEW_GROUP_FORMAT_OPTION}, + {"new-line-format", 1, 0, NEW_LINE_FORMAT_OPTION}, + {"no-dereference", 0, 0, NO_DEREFERENCE_OPTION}, + {"no-ignore-file-name-case", 0, 0, NO_IGNORE_FILE_NAME_CASE_OPTION}, + {"normal", 0, 0, NORMAL_OPTION}, + {"old-group-format", 1, 0, OLD_GROUP_FORMAT_OPTION}, + {"old-line-format", 1, 0, OLD_LINE_FORMAT_OPTION}, + {"paginate", 0, 0, 'l'}, + {"palette", 1, 0, COLOR_PALETTE_OPTION}, + {"rcs", 0, 0, 'n'}, + {"recursive", 0, 0, 'r'}, + {"report-identical-files", 0, 0, 's'}, + {"sdiff-merge-assist", 0, 0, SDIFF_MERGE_ASSIST_OPTION}, + {"show-c-function", 0, 0, 'p'}, + {"show-function-line", 1, 0, 'F'}, + {"side-by-side", 0, 0, 'y'}, + {"speed-large-files", 0, 0, 'H'}, + {"starting-file", 1, 0, 'S'}, + {"strip-trailing-cr", 0, 0, STRIP_TRAILING_CR_OPTION}, + {"suppress-blank-empty", 0, 0, SUPPRESS_BLANK_EMPTY_OPTION}, + {"suppress-common-lines", 0, 0, SUPPRESS_COMMON_LINES_OPTION}, + {"tabsize", 1, 0, TABSIZE_OPTION}, + {"text", 0, 0, 'a'}, + {"to-file", 1, 0, TO_FILE_OPTION}, + {"unchanged-group-format", 1, 0, UNCHANGED_GROUP_FORMAT_OPTION}, + {"unchanged-line-format", 1, 0, UNCHANGED_LINE_FORMAT_OPTION}, + {"unidirectional-new-file", 0, 0, 'P'}, + {"unified", 2, 0, 'U'}, + {"version", 0, 0, 'v'}, + {"width", 1, 0, 'W'}, + + /* This is solely for testing. Do not document. */ + {"-presume-output-tty", no_argument, NULL, PRESUME_OUTPUT_TTY_OPTION}, + {0, 0, 0, 0} +}; + +/* Return a string containing the command options with which diff was invoked. + Spaces appear between what were separate ARGV-elements. + There is a space at the beginning but none at the end. + If there were no options, the result is an empty string. + + Arguments: OPTIONVEC, a vector containing separate ARGV-elements, and COUNT, + the length of that vector. */ + +static char * +option_list (char **optionvec, int count) +{ + int i; + size_t size = 1; + char *result; + char *p; + + for (i = 0; i < count; i++) + size += 1 + shell_quote_length (optionvec[i]); + + p = result = xmalloc (size); + + for (i = 0; i < count; i++) + { + *p++ = ' '; + p = shell_quote_copy (p, optionvec[i]); + } + + *p = '\0'; + return result; +} + + +/* Return an option value suitable for add_exclude. */ + +static int +exclude_options (void) +{ + return EXCLUDE_WILDCARDS | (ignore_file_name_case ? FNM_CASEFOLD : 0); +} + +int +main (int argc, char **argv) +{ + int exit_status = EXIT_SUCCESS; + int c; + int i; + int prev = -1; + lin ocontext = -1; + bool explicit_context = false; + size_t width = 0; + bool show_c_function = false; + char const *from_file = NULL; + char const *to_file = NULL; + uintmax_t numval; + char *numend; + + /* Do our initializations. */ + exit_failure = EXIT_TROUBLE; + initialize_main (&argc, &argv); + set_program_name (argv[0]); + setlocale (LC_ALL, ""); + bindtextdomain (PACKAGE, LOCALEDIR); + textdomain (PACKAGE); + c_stack_action (0); + function_regexp_list.buf = &function_regexp; + ignore_regexp_list.buf = &ignore_regexp; + re_set_syntax (RE_SYNTAX_GREP | RE_NO_POSIX_BACKTRACKING); + excluded = new_exclude (); + + /* Decode the options. */ + + while ((c = getopt_long (argc, argv, shortopts, longopts, NULL)) != -1) + { + switch (c) + { + case 0: + break; + + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + ocontext = (! ISDIGIT (prev) + ? c - '0' + : (ocontext - (c - '0' <= CONTEXT_MAX % 10) + < CONTEXT_MAX / 10) + ? 10 * ocontext + (c - '0') + : CONTEXT_MAX); + break; + + case 'a': + text = true; + break; + + case 'b': + if (ignore_white_space < IGNORE_SPACE_CHANGE) + ignore_white_space = IGNORE_SPACE_CHANGE; + break; + + case 'Z': + if (ignore_white_space < IGNORE_SPACE_CHANGE) + ignore_white_space |= IGNORE_TRAILING_SPACE; + break; + + case 'B': + ignore_blank_lines = true; + break; + + case 'C': + case 'U': + { + if (optarg) + { + numval = strtoumax (optarg, &numend, 10); + if (*numend) + try_help ("invalid context length '%s'", optarg); + if (CONTEXT_MAX < numval) + numval = CONTEXT_MAX; + } + else + numval = 3; + + specify_style (c == 'U' ? OUTPUT_UNIFIED : OUTPUT_CONTEXT); + if (context < numval) + context = numval; + explicit_context = true; + } + break; + + case 'c': + specify_style (OUTPUT_CONTEXT); + if (context < 3) + context = 3; + break; + + case 'd': + minimal = true; + break; + + case 'D': + specify_style (OUTPUT_IFDEF); + { + static char const C_ifdef_group_formats[] = + "%%=%c#ifndef %s\n%%<#endif /* ! %s */\n%c#ifdef %s\n%%>#endif /* %s */\n%c#ifndef %s\n%%<#else /* %s */\n%%>#endif /* %s */\n"; + char *b = xmalloc (sizeof C_ifdef_group_formats + + 7 * strlen (optarg) - 14 /* 7*"%s" */ + - 8 /* 5*"%%" + 3*"%c" */); + sprintf (b, C_ifdef_group_formats, + 0, + optarg, optarg, 0, + optarg, optarg, 0, + optarg, optarg, optarg); + for (i = 0; i < sizeof group_format / sizeof group_format[0]; i++) + { + specify_value (&group_format[i], b, "-D"); + b += strlen (b) + 1; + } + } + break; + + case 'e': + specify_style (OUTPUT_ED); + break; + + case 'E': + if (ignore_white_space < IGNORE_SPACE_CHANGE) + ignore_white_space |= IGNORE_TAB_EXPANSION; + break; + + case 'f': + specify_style (OUTPUT_FORWARD_ED); + break; + + case 'F': + add_regexp (&function_regexp_list, optarg); + break; + + case 'h': + /* Split the files into chunks for faster processing. + Usually does not change the result. + + This currently has no effect. */ + break; + + case 'H': + speed_large_files = true; + break; + + case 'i': + ignore_case = true; + break; + + case 'I': + add_regexp (&ignore_regexp_list, optarg); + break; + + case 'l': + if (!pr_program[0]) + try_help ("pagination not supported on this host", NULL); + paginate = true; +#ifdef SIGCHLD + /* Pagination requires forking and waiting, and + System V fork+wait does not work if SIGCHLD is ignored. */ + signal (SIGCHLD, SIG_DFL); +#endif + break; + + case 'L': + if (!file_label[0]) + file_label[0] = optarg; + else if (!file_label[1]) + file_label[1] = optarg; + else + fatal ("too many file label options"); + break; + + case 'n': + specify_style (OUTPUT_RCS); + break; + + case 'N': + new_file = true; + break; + + case 'p': + show_c_function = true; + add_regexp (&function_regexp_list, "^[[:alpha:]$_]"); + break; + + case 'P': + unidirectional_new_file = true; + break; + + case 'q': + brief = true; + break; + + case 'r': + recursive = true; + break; + + case 's': + report_identical_files = true; + break; + + case 'S': + specify_value (&starting_file, optarg, "-S"); + break; + + case 't': + expand_tabs = true; + break; + + case 'T': + initial_tab = true; + break; + + case 'u': + specify_style (OUTPUT_UNIFIED); + if (context < 3) + context = 3; + break; + + case 'v': + version_etc (stdout, PROGRAM_NAME, PACKAGE_NAME, Version, + AUTHORS, (char *) NULL); + check_stdout (); + return EXIT_SUCCESS; + + case 'w': + ignore_white_space = IGNORE_ALL_SPACE; + break; + + case 'x': + add_exclude (excluded, optarg, exclude_options ()); + break; + + case 'X': + if (add_exclude_file (add_exclude, excluded, optarg, + exclude_options (), '\n')) + pfatal_with_name (optarg); + break; + + case 'y': + specify_style (OUTPUT_SDIFF); + break; + + case 'W': + numval = strtoumax (optarg, &numend, 10); + if (! (0 < numval && numval <= SIZE_MAX) || *numend) + try_help ("invalid width '%s'", optarg); + if (width != numval) + { + if (width) + fatal ("conflicting width options"); + width = numval; + } + break; + + case BINARY_OPTION: +#if O_BINARY + binary = true; + if (! isatty (STDOUT_FILENO)) + set_binary_mode (STDOUT_FILENO, O_BINARY); +#endif + break; + + case FROM_FILE_OPTION: + specify_value (&from_file, optarg, "--from-file"); + break; + + case HELP_OPTION: + usage (); + check_stdout (); + return EXIT_SUCCESS; + + case HORIZON_LINES_OPTION: + numval = strtoumax (optarg, &numend, 10); + if (*numend) + try_help ("invalid horizon length '%s'", optarg); + horizon_lines = MAX (horizon_lines, MIN (numval, LIN_MAX)); + break; + + case IGNORE_FILE_NAME_CASE_OPTION: + ignore_file_name_case = true; + break; + + case INHIBIT_HUNK_MERGE_OPTION: + /* This option is obsolete, but accept it for backward + compatibility. */ + break; + + case LEFT_COLUMN_OPTION: + left_column = true; + break; + + case LINE_FORMAT_OPTION: + specify_style (OUTPUT_IFDEF); + for (i = 0; i < sizeof line_format / sizeof line_format[0]; i++) + specify_value (&line_format[i], optarg, "--line-format"); + break; + + case NO_DEREFERENCE_OPTION: + no_dereference_symlinks = true; + break; + + case NO_IGNORE_FILE_NAME_CASE_OPTION: + ignore_file_name_case = false; + break; + + case NORMAL_OPTION: + specify_style (OUTPUT_NORMAL); + break; + + case SDIFF_MERGE_ASSIST_OPTION: + specify_style (OUTPUT_SDIFF); + sdiff_merge_assist = true; + break; + + case STRIP_TRAILING_CR_OPTION: + strip_trailing_cr = true; + break; + + case SUPPRESS_BLANK_EMPTY_OPTION: + suppress_blank_empty = true; + break; + + case SUPPRESS_COMMON_LINES_OPTION: + suppress_common_lines = true; + break; + + case TABSIZE_OPTION: + numval = strtoumax (optarg, &numend, 10); + if (! (0 < numval && numval <= SIZE_MAX - GUTTER_WIDTH_MINIMUM) + || *numend) + try_help ("invalid tabsize '%s'", optarg); + if (tabsize != numval) + { + if (tabsize) + fatal ("conflicting tabsize options"); + tabsize = numval; + } + break; + + case TO_FILE_OPTION: + specify_value (&to_file, optarg, "--to-file"); + break; + + case UNCHANGED_LINE_FORMAT_OPTION: + case OLD_LINE_FORMAT_OPTION: + case NEW_LINE_FORMAT_OPTION: + specify_style (OUTPUT_IFDEF); + c -= UNCHANGED_LINE_FORMAT_OPTION; + specify_value (&line_format[c], optarg, line_format_option[c]); + break; + + case UNCHANGED_GROUP_FORMAT_OPTION: + case OLD_GROUP_FORMAT_OPTION: + case NEW_GROUP_FORMAT_OPTION: + case CHANGED_GROUP_FORMAT_OPTION: + specify_style (OUTPUT_IFDEF); + c -= UNCHANGED_GROUP_FORMAT_OPTION; + specify_value (&group_format[c], optarg, group_format_option[c]); + break; + + case COLOR_OPTION: + specify_colors_style (optarg); + break; + + case COLOR_PALETTE_OPTION: + set_color_palette (optarg); + break; + + case PRESUME_OUTPUT_TTY_OPTION: + presume_output_tty = true; + break; + + default: + try_help (NULL, NULL); + } + prev = c; + } + + if (colors_style == AUTO) + { + char const *t = getenv ("TERM"); + if (t && STREQ (t, "dumb")) + colors_style = NEVER; + } + + if (output_style == OUTPUT_UNSPECIFIED) + { + if (show_c_function) + { + specify_style (OUTPUT_CONTEXT); + if (ocontext < 0) + context = 3; + } + else + specify_style (OUTPUT_NORMAL); + } + + if (output_style != OUTPUT_CONTEXT || hard_locale (LC_TIME)) + { +#if (defined STAT_TIMESPEC || defined STAT_TIMESPEC_NS \ + || defined HAVE_STRUCT_STAT_ST_SPARE1) + time_format = "%Y-%m-%d %H:%M:%S.%N %z"; +#else + time_format = "%Y-%m-%d %H:%M:%S %z"; +#endif + } + else + { + /* See POSIX 1003.1-2001 for this format. */ + time_format = "%a %b %e %T %Y"; + } + + if (0 <= ocontext + && (output_style == OUTPUT_CONTEXT + || output_style == OUTPUT_UNIFIED) + && (context < ocontext + || (ocontext < context && ! explicit_context))) + context = ocontext; + + if (! tabsize) + tabsize = 8; + if (! width) + width = 130; + + { + /* Maximize first the half line width, and then the gutter width, + according to the following constraints: + + 1. Two half lines plus a gutter must fit in a line. + 2. If the half line width is nonzero: + a. The gutter width is at least GUTTER_WIDTH_MINIMUM. + b. If tabs are not expanded to spaces, + a half line plus a gutter is an integral number of tabs, + so that tabs in the right column line up. */ + + size_t t = expand_tabs ? 1 : tabsize; + size_t w = width; + size_t t_plus_g = t + GUTTER_WIDTH_MINIMUM; + size_t unaligned_off = (w >> 1) + (t_plus_g >> 1) + (w & t_plus_g & 1); + size_t off = unaligned_off - unaligned_off % t; + sdiff_half_width = (off <= GUTTER_WIDTH_MINIMUM || w <= off + ? 0 + : MIN (off - GUTTER_WIDTH_MINIMUM, w - off)); + sdiff_column2_offset = sdiff_half_width ? off : w; + } + + /* Make the horizon at least as large as the context, so that + shift_boundaries has more freedom to shift the first and last hunks. */ + if (horizon_lines < context) + horizon_lines = context; + + summarize_regexp_list (&function_regexp_list); + summarize_regexp_list (&ignore_regexp_list); + + if (output_style == OUTPUT_IFDEF) + { + for (i = 0; i < sizeof line_format / sizeof line_format[0]; i++) + if (!line_format[i]) + line_format[i] = "%l\n"; + if (!group_format[OLD]) + group_format[OLD] + = group_format[CHANGED] ? group_format[CHANGED] : "%<"; + if (!group_format[NEW]) + group_format[NEW] + = group_format[CHANGED] ? group_format[CHANGED] : "%>"; + if (!group_format[UNCHANGED]) + group_format[UNCHANGED] = "%="; + if (!group_format[CHANGED]) + group_format[CHANGED] = concat (group_format[OLD], + group_format[NEW], ""); + } + + no_diff_means_no_output = + (output_style == OUTPUT_IFDEF ? + (!*group_format[UNCHANGED] + || (STREQ (group_format[UNCHANGED], "%=") + && !*line_format[UNCHANGED])) + : (output_style != OUTPUT_SDIFF) | suppress_common_lines); + + files_can_be_treated_as_binary = + (brief & binary + & ~ (ignore_blank_lines | ignore_case | strip_trailing_cr + | (ignore_regexp_list.regexps || ignore_white_space))); + + switch_string = option_list (argv + 1, optind - 1); + + if (from_file) + { + if (to_file) + fatal ("--from-file and --to-file both specified"); + else + for (; optind < argc; optind++) + { + int status = compare_files (NULL, from_file, argv[optind]); + if (exit_status < status) + exit_status = status; + } + } + else + { + if (to_file) + for (; optind < argc; optind++) + { + int status = compare_files (NULL, argv[optind], to_file); + if (exit_status < status) + exit_status = status; + } + else + { + if (argc - optind != 2) + { + if (argc - optind < 2) + try_help ("missing operand after '%s'", argv[argc - 1]); + else + try_help ("extra operand '%s'", argv[optind + 2]); + } + + exit_status = compare_files (NULL, argv[optind], argv[optind + 1]); + } + } + + /* Print any messages that were saved up for last. */ + print_message_queue (); + + check_stdout (); + exit (exit_status); + return exit_status; +} + +/* Append to REGLIST the regexp PATTERN. */ + +static void +add_regexp (struct regexp_list *reglist, char const *pattern) +{ + size_t patlen = strlen (pattern); + char const *m = re_compile_pattern (pattern, patlen, reglist->buf); + + if (m != 0) + error (0, 0, "%s: %s", pattern, m); + else + { + char *regexps = reglist->regexps; + size_t len = reglist->len; + bool multiple_regexps = reglist->multiple_regexps = regexps != 0; + size_t newlen = reglist->len = len + 2 * multiple_regexps + patlen; + size_t size = reglist->size; + + if (size <= newlen) + { + if (!size) + size = 1; + + do size *= 2; + while (size <= newlen); + + reglist->size = size; + reglist->regexps = regexps = xrealloc (regexps, size); + } + if (multiple_regexps) + { + regexps[len++] = '\\'; + regexps[len++] = '|'; + } + memcpy (regexps + len, pattern, patlen + 1); + } +} + +/* Ensure that REGLIST represents the disjunction of its regexps. + This is done here, rather than earlier, to avoid O(N^2) behavior. */ + +static void +summarize_regexp_list (struct regexp_list *reglist) +{ + if (reglist->regexps) + { + /* At least one regexp was specified. Allocate a fastmap for it. */ + reglist->buf->fastmap = xmalloc (1 << CHAR_BIT); + if (reglist->multiple_regexps) + { + /* Compile the disjunction of the regexps. + (If just one regexp was specified, it is already compiled.) */ + char const *m = re_compile_pattern (reglist->regexps, reglist->len, + reglist->buf); + if (m) + error (EXIT_TROUBLE, 0, "%s: %s", reglist->regexps, m); + } + } +} + +static void +try_help (char const *reason_msgid, char const *operand) +{ + if (reason_msgid) + error (0, 0, _(reason_msgid), operand); + error (EXIT_TROUBLE, 0, _("Try '%s --help' for more information."), + program_name); + abort (); +} + +static void +check_stdout (void) +{ + if (ferror (stdout)) + fatal ("write failed"); + else if (fclose (stdout) != 0) + pfatal_with_name (_("standard output")); +} + +static char const * const option_help_msgid[] = { + N_(" --normal output a normal diff (the default)"), + N_("-q, --brief report only when files differ"), + N_("-s, --report-identical-files report when two files are the same"), + N_("-c, -C NUM, --context[=NUM] output NUM (default 3) lines of copied context"), + N_("-u, -U NUM, --unified[=NUM] output NUM (default 3) lines of unified context"), + N_("-e, --ed output an ed script"), + N_("-n, --rcs output an RCS format diff"), + N_("-y, --side-by-side output in two columns"), + N_("-W, --width=NUM output at most NUM (default 130) print columns"), + N_(" --left-column output only the left column of common lines"), + N_(" --suppress-common-lines do not output common lines"), + "", + N_("-p, --show-c-function show which C function each change is in"), + N_("-F, --show-function-line=RE show the most recent line matching RE"), + N_(" --label LABEL use LABEL instead of file name and timestamp\n" + " (can be repeated)"), + "", + N_("-t, --expand-tabs expand tabs to spaces in output"), + N_("-T, --initial-tab make tabs line up by prepending a tab"), + N_(" --tabsize=NUM tab stops every NUM (default 8) print columns"), + N_(" --suppress-blank-empty suppress space or tab before empty output lines"), + N_("-l, --paginate pass output through 'pr' to paginate it"), + "", + N_("-r, --recursive recursively compare any subdirectories found"), + N_(" --no-dereference don't follow symbolic links"), + N_("-N, --new-file treat absent files as empty"), + N_(" --unidirectional-new-file treat absent first files as empty"), + N_(" --ignore-file-name-case ignore case when comparing file names"), + N_(" --no-ignore-file-name-case consider case when comparing file names"), + N_("-x, --exclude=PAT exclude files that match PAT"), + N_("-X, --exclude-from=FILE exclude files that match any pattern in FILE"), + N_("-S, --starting-file=FILE start with FILE when comparing directories"), + N_(" --from-file=FILE1 compare FILE1 to all operands;\n" + " FILE1 can be a directory"), + N_(" --to-file=FILE2 compare all operands to FILE2;\n" + " FILE2 can be a directory"), + "", + N_("-i, --ignore-case ignore case differences in file contents"), + N_("-E, --ignore-tab-expansion ignore changes due to tab expansion"), + N_("-Z, --ignore-trailing-space ignore white space at line end"), + N_("-b, --ignore-space-change ignore changes in the amount of white space"), + N_("-w, --ignore-all-space ignore all white space"), + N_("-B, --ignore-blank-lines ignore changes where lines are all blank"), + N_("-I, --ignore-matching-lines=RE ignore changes where all lines match RE"), + "", + N_("-a, --text treat all files as text"), + N_(" --strip-trailing-cr strip trailing carriage return on input"), +#if O_BINARY + N_(" --binary read and write data in binary mode"), +#endif + "", + N_("-D, --ifdef=NAME output merged file with '#ifdef NAME' diffs"), + N_(" --GTYPE-group-format=GFMT format GTYPE input groups with GFMT"), + N_(" --line-format=LFMT format all input lines with LFMT"), + N_(" --LTYPE-line-format=LFMT format LTYPE input lines with LFMT"), + N_(" These format options provide fine-grained control over the output\n" + " of diff, generalizing -D/--ifdef."), + N_(" LTYPE is 'old', 'new', or 'unchanged'. GTYPE is LTYPE or 'changed'."), + N_(" GFMT (only) may contain:\n\ + %< lines from FILE1\n\ + %> lines from FILE2\n\ + %= lines common to FILE1 and FILE2\n\ + %[-][WIDTH][.[PREC]]{doxX}LETTER printf-style spec for LETTER\n\ + LETTERs are as follows for new group, lower case for old group:\n\ + F first line number\n\ + L last line number\n\ + N number of lines = L-F+1\n\ + E F-1\n\ + M L+1\n\ + %(A=B?T:E) if A equals B then T else E"), + N_(" LFMT (only) may contain:\n\ + %L contents of line\n\ + %l contents of line, excluding any trailing newline\n\ + %[-][WIDTH][.[PREC]]{doxX}n printf-style spec for input line number"), + N_(" Both GFMT and LFMT may contain:\n\ + %% %\n\ + %c'C' the single character C\n\ + %c'\\OOO' the character with octal code OOO\n\ + C the character C (other characters represent themselves)"), + "", + N_("-d, --minimal try hard to find a smaller set of changes"), + N_(" --horizon-lines=NUM keep NUM lines of the common prefix and suffix"), + N_(" --speed-large-files assume large files and many scattered small changes"), + N_(" --color[=WHEN] colorize the output; WHEN can be 'never', 'always',"), + N_(" or 'auto' (the default)"), + N_(" --palette=PALETTE specify the colors to use when --color is active"), + N_(" PALETTE is a colon-separated list terminfo capabilities"), + "", + N_(" --help display this help and exit"), + N_("-v, --version output version information and exit"), + "", + N_("FILES are 'FILE1 FILE2' or 'DIR1 DIR2' or 'DIR FILE' or 'FILE DIR'."), + N_("If --from-file or --to-file is given, there are no restrictions on FILE(s)."), + N_("If a FILE is '-', read standard input."), + N_("Exit status is 0 if inputs are the same, 1 if different, 2 if trouble."), + 0 +}; + +static void +usage (void) +{ + char const * const *p; + + printf (_("Usage: %s [OPTION]... FILES\n"), program_name); + printf ("%s\n\n", _("Compare FILES line by line.")); + + fputs (_("\ +Mandatory arguments to long options are mandatory for short options too.\n\ +"), stdout); + + for (p = option_help_msgid; *p; p++) + { + if (!**p) + putchar ('\n'); + else + { + char const *msg = _(*p); + char const *nl; + while ((nl = strchr (msg, '\n'))) + { + int msglen = nl + 1 - msg; + printf (" %.*s", msglen, msg); + msg = nl + 1; + } + + printf (" %s\n" + 2 * (*msg != ' ' && *msg != '-'), msg); + } + } + emit_bug_reporting_address (); +} + +/* Set VAR to VALUE, reporting an OPTION error if this is a + conflict. */ +static void +specify_value (char const **var, char const *value, char const *option) +{ + if (*var && ! STREQ (*var, value)) + { + error (0, 0, _("conflicting %s option value '%s'"), option, value); + try_help (NULL, NULL); + } + *var = value; +} + +/* Set the output style to STYLE, diagnosing conflicts. */ +static void +specify_style (enum output_style style) +{ + if (output_style != style) + { + if (output_style != OUTPUT_UNSPECIFIED) + try_help ("conflicting output style options", NULL); + output_style = style; + } +} + +/* Set the color mode. */ +static void +specify_colors_style (char const *value) +{ + if (value == NULL || STREQ (value, "auto")) + colors_style = AUTO; + else if (STREQ (value, "always")) + colors_style = ALWAYS; + else if (STREQ (value, "never")) + colors_style = NEVER; + else + try_help ("invalid color '%s'", value); +} + + +/* Set the last-modified time of *ST to be the current time. */ + +static void +set_mtime_to_now (struct stat *st) +{ +#ifdef STAT_TIMESPEC + gettime (&STAT_TIMESPEC (st, st_mtim)); +#else + struct timespec t; + gettime (&t); + st->st_mtime = t.tv_sec; +# if defined STAT_TIMESPEC_NS + STAT_TIMESPEC_NS (st, st_mtim) = t.tv_nsec; +# elif defined HAVE_STRUCT_STAT_ST_SPARE1 + st->st_spare1 = t.tv_nsec / 1000; +# endif +#endif +} + +/* Compare two files (or dirs) with parent comparison PARENT + and names NAME0 and NAME1. + (If PARENT is null, then the first name is just NAME0, etc.) + This is self-contained; it opens the files and closes them. + + Value is EXIT_SUCCESS if files are the same, EXIT_FAILURE if + different, EXIT_TROUBLE if there is a problem opening them. */ + +static int +compare_files (struct comparison const *parent, + char const *name0, + char const *name1) +{ + struct comparison cmp; +#define DIR_P(f) (S_ISDIR (cmp.file[f].stat.st_mode) != 0) + register int f; + int status = EXIT_SUCCESS; + bool same_files; + char *free0; + char *free1; + + /* If this is directory comparison, perhaps we have a file + that exists only in one of the directories. + If so, just print a message to that effect. */ + + if (! ((name0 && name1) + || (unidirectional_new_file && name1) + || new_file)) + { + char const *name = name0 ? name0 : name1; + char const *dir = parent->file[!name0].name; + + /* See POSIX 1003.1-2001 for this format. */ + message ("Only in %s: %s\n", dir, name); + + /* Return EXIT_FAILURE so that diff_dirs will return + EXIT_FAILURE ("some files differ"). */ + return EXIT_FAILURE; + } + + memset (cmp.file, 0, sizeof cmp.file); + cmp.parent = parent; + + /* cmp.file[f].desc markers */ +#define NONEXISTENT (-1) /* nonexistent file */ +#define UNOPENED (-2) /* unopened file (e.g. directory) */ +#define ERRNO_ENCODE(errno) (-3 - (errno)) /* encoded errno value */ + +#define ERRNO_DECODE(desc) (-3 - (desc)) /* inverse of ERRNO_ENCODE */ + + cmp.file[0].desc = name0 ? UNOPENED : NONEXISTENT; + cmp.file[1].desc = name1 ? UNOPENED : NONEXISTENT; + + /* Now record the full name of each file, including nonexistent ones. */ + + if (!name0) + name0 = name1; + if (!name1) + name1 = name0; + + if (!parent) + { + free0 = NULL; + free1 = NULL; + cmp.file[0].name = name0; + cmp.file[1].name = name1; + } + else + { + cmp.file[0].name = free0 + = file_name_concat (parent->file[0].name, name0, NULL); + cmp.file[1].name = free1 + = file_name_concat (parent->file[1].name, name1, NULL); + } + + /* Stat the files. */ + + for (f = 0; f < 2; f++) + { + if (cmp.file[f].desc != NONEXISTENT) + { + if (f && file_name_cmp (cmp.file[f].name, cmp.file[0].name) == 0) + { + cmp.file[f].desc = cmp.file[0].desc; + cmp.file[f].stat = cmp.file[0].stat; + } + else if (STREQ (cmp.file[f].name, "-")) + { + cmp.file[f].desc = STDIN_FILENO; + if (binary && ! isatty (STDIN_FILENO)) + set_binary_mode (STDIN_FILENO, O_BINARY); + if (fstat (STDIN_FILENO, &cmp.file[f].stat) != 0) + cmp.file[f].desc = ERRNO_ENCODE (errno); + else + { + if (S_ISREG (cmp.file[f].stat.st_mode)) + { + off_t pos = lseek (STDIN_FILENO, 0, SEEK_CUR); + if (pos < 0) + cmp.file[f].desc = ERRNO_ENCODE (errno); + else + cmp.file[f].stat.st_size = + MAX (0, cmp.file[f].stat.st_size - pos); + } + + /* POSIX 1003.1-2001 requires current time for + stdin. */ + set_mtime_to_now (&cmp.file[f].stat); + } + } + else if ((no_dereference_symlinks + ? lstat (cmp.file[f].name, &cmp.file[f].stat) + : stat (cmp.file[f].name, &cmp.file[f].stat)) + != 0) + cmp.file[f].desc = ERRNO_ENCODE (errno); + } + } + + /* Mark files as nonexistent as needed for -N and -P, if they are + inaccessible empty regular files (the kind of files that 'patch' + creates to indicate nonexistent backups), or if they are + top-level files that do not exist but their counterparts do + exist. */ + for (f = 0; f < 2; f++) + if ((new_file || (f == 0 && unidirectional_new_file)) + && (cmp.file[f].desc == UNOPENED + ? (S_ISREG (cmp.file[f].stat.st_mode) + && ! (cmp.file[f].stat.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO)) + && cmp.file[f].stat.st_size == 0) + : ((cmp.file[f].desc == ERRNO_ENCODE (ENOENT) + || cmp.file[f].desc == ERRNO_ENCODE (EBADF)) + && ! parent + && (cmp.file[1 - f].desc == UNOPENED + || cmp.file[1 - f].desc == STDIN_FILENO)))) + cmp.file[f].desc = NONEXISTENT; + + for (f = 0; f < 2; f++) + if (cmp.file[f].desc == NONEXISTENT) + { + memset (&cmp.file[f].stat, 0, sizeof cmp.file[f].stat); + cmp.file[f].stat.st_mode = cmp.file[1 - f].stat.st_mode; + } + + for (f = 0; f < 2; f++) + { + int e = ERRNO_DECODE (cmp.file[f].desc); + if (0 <= e) + { + errno = e; + perror_with_name (cmp.file[f].name); + status = EXIT_TROUBLE; + } + } + + if (status == EXIT_SUCCESS && ! parent && DIR_P (0) != DIR_P (1)) + { + /* If one is a directory, and it was specified in the command line, + use the file in that dir with the other file's basename. */ + + int fnm_arg = DIR_P (0); + int dir_arg = 1 - fnm_arg; + char const *fnm = cmp.file[fnm_arg].name; + char const *dir = cmp.file[dir_arg].name; + char const *filename = cmp.file[dir_arg].name = free0 + = find_dir_file_pathname (dir, last_component (fnm)); + + if (STREQ (fnm, "-")) + fatal ("cannot compare '-' to a directory"); + + if ((no_dereference_symlinks + ? lstat (filename, &cmp.file[dir_arg].stat) + : stat (filename, &cmp.file[dir_arg].stat)) + != 0) + { + perror_with_name (filename); + status = EXIT_TROUBLE; + } + } + + if (status != EXIT_SUCCESS) + { + /* One of the files should exist but does not. */ + } + else if (cmp.file[0].desc == NONEXISTENT + && cmp.file[1].desc == NONEXISTENT) + { + /* Neither file "exists", so there's nothing to compare. */ + } + else if ((same_files + = (cmp.file[0].desc != NONEXISTENT + && cmp.file[1].desc != NONEXISTENT + && 0 < same_file (&cmp.file[0].stat, &cmp.file[1].stat) + && same_file_attributes (&cmp.file[0].stat, + &cmp.file[1].stat))) + && no_diff_means_no_output) + { + /* The two named files are actually the same physical file. + We know they are identical without actually reading them. */ + } + else if (DIR_P (0) & DIR_P (1)) + { + if (output_style == OUTPUT_IFDEF) + fatal ("-D option not supported with directories"); + + /* If both are directories, compare the files in them. */ + + if (parent && !recursive) + { + /* But don't compare dir contents one level down + unless -r was specified. + See POSIX 1003.1-2001 for this format. */ + message ("Common subdirectories: %s and %s\n", + cmp.file[0].name, cmp.file[1].name); + } + else + status = diff_dirs (&cmp, compare_files); + } + else if ((DIR_P (0) | DIR_P (1)) + || (parent + && !((S_ISREG (cmp.file[0].stat.st_mode) + || S_ISLNK (cmp.file[0].stat.st_mode)) + && (S_ISREG (cmp.file[1].stat.st_mode) + || S_ISLNK (cmp.file[1].stat.st_mode))))) + { + if (cmp.file[0].desc == NONEXISTENT || cmp.file[1].desc == NONEXISTENT) + { + /* We have a subdirectory that exists only in one directory. */ + + if ((DIR_P (0) | DIR_P (1)) + && recursive + && (new_file + || (unidirectional_new_file + && cmp.file[0].desc == NONEXISTENT))) + status = diff_dirs (&cmp, compare_files); + else + { + char const *dir; + + /* PARENT must be non-NULL here. */ + assert (parent); + dir = parent->file[cmp.file[0].desc == NONEXISTENT].name; + + /* See POSIX 1003.1-2001 for this format. */ + message ("Only in %s: %s\n", dir, name0); + + status = EXIT_FAILURE; + } + } + else + { + /* We have two files that are not to be compared. */ + + /* See POSIX 1003.1-2001 for this format. */ + message5 ("File %s is a %s while file %s is a %s\n", + file_label[0] ? file_label[0] : cmp.file[0].name, + file_type (&cmp.file[0].stat), + file_label[1] ? file_label[1] : cmp.file[1].name, + file_type (&cmp.file[1].stat)); + + /* This is a difference. */ + status = EXIT_FAILURE; + } + } + else if (S_ISLNK (cmp.file[0].stat.st_mode) + || S_ISLNK (cmp.file[1].stat.st_mode)) + { + /* We get here only if we use lstat(), not stat(). */ + assert (no_dereference_symlinks); + + if (S_ISLNK (cmp.file[0].stat.st_mode) + && S_ISLNK (cmp.file[1].stat.st_mode)) + { + /* Compare the values of the symbolic links. */ + char *link_value[2] = { NULL, NULL }; + + for (f = 0; f < 2; f++) + { + link_value[f] = xreadlink (cmp.file[f].name); + if (link_value[f] == NULL) + { + perror_with_name (cmp.file[f].name); + status = EXIT_TROUBLE; + break; + } + } + if (status == EXIT_SUCCESS) + { + if ( ! STREQ (link_value[0], link_value[1])) + { + message ("Symbolic links %s and %s differ\n", + cmp.file[0].name, cmp.file[1].name); + /* This is a difference. */ + status = EXIT_FAILURE; + } + } + for (f = 0; f < 2; f++) + free (link_value[f]); + } + else + { + /* We have two files that are not to be compared, because + one of them is a symbolic link and the other one is not. */ + + message5 ("File %s is a %s while file %s is a %s\n", + file_label[0] ? file_label[0] : cmp.file[0].name, + file_type (&cmp.file[0].stat), + file_label[1] ? file_label[1] : cmp.file[1].name, + file_type (&cmp.file[1].stat)); + + /* This is a difference. */ + status = EXIT_FAILURE; + } + } + else if (files_can_be_treated_as_binary + && S_ISREG (cmp.file[0].stat.st_mode) + && S_ISREG (cmp.file[1].stat.st_mode) + && cmp.file[0].stat.st_size != cmp.file[1].stat.st_size + && 0 < cmp.file[0].stat.st_size + && 0 < cmp.file[1].stat.st_size) + { + message ("Files %s and %s differ\n", + file_label[0] ? file_label[0] : cmp.file[0].name, + file_label[1] ? file_label[1] : cmp.file[1].name); + status = EXIT_FAILURE; + } + else + { + /* Both exist and neither is a directory. */ + + /* Open the files and record their descriptors. */ + + int oflags = O_RDONLY | (binary ? O_BINARY : 0); + + if (cmp.file[0].desc == UNOPENED) + if ((cmp.file[0].desc = open (cmp.file[0].name, oflags, 0)) < 0) + { + perror_with_name (cmp.file[0].name); + status = EXIT_TROUBLE; + } + if (cmp.file[1].desc == UNOPENED) + { + if (same_files) + cmp.file[1].desc = cmp.file[0].desc; + else if ((cmp.file[1].desc = open (cmp.file[1].name, oflags, 0)) < 0) + { + perror_with_name (cmp.file[1].name); + status = EXIT_TROUBLE; + } + } + + /* Compare the files, if no error was found. */ + + if (status == EXIT_SUCCESS) + status = diff_2_files (&cmp); + + /* Close the file descriptors. */ + + if (0 <= cmp.file[0].desc && close (cmp.file[0].desc) != 0) + { + perror_with_name (cmp.file[0].name); + status = EXIT_TROUBLE; + } + if (0 <= cmp.file[1].desc && cmp.file[0].desc != cmp.file[1].desc + && close (cmp.file[1].desc) != 0) + { + perror_with_name (cmp.file[1].name); + status = EXIT_TROUBLE; + } + } + + /* Now the comparison has been done, if no error prevented it, + and STATUS is the value this function will return. */ + + if (status == EXIT_SUCCESS) + { + if (report_identical_files && !DIR_P (0)) + message ("Files %s and %s are identical\n", + file_label[0] ? file_label[0] : cmp.file[0].name, + file_label[1] ? file_label[1] : cmp.file[1].name); + } + else + { + /* Flush stdout so that the user sees differences immediately. + This can hurt performance, unfortunately. */ + if (fflush (stdout) != 0) + pfatal_with_name (_("standard output")); + } + + free (free0); + free (free1); + + return status; +} |